Search Results

You are looking at 1 - 4 of 4 items for

  • Author: Qisheng Li x
Clear All Modify Search
Open access

Mingxiang Ling, Huimin Li and Qisheng Li

Abstract

Measurement uncertainty evaluation based on the Monte Carlo method (MCM) with the assumption that all uncertainty sources are independent is common. For some measure problems, however, the correlation between input quantities is of great importance and even essential. The purpose of this paper is to provide an uncertainty evaluation method based on MCM that can handle correlated cases, especially for measurement in which uncertainty sources are correlated and submit to non-Gaussian distribution. In this method, a linear-nonlinear transformation technique was developed to generate correlated random variables sampling sequences with target prescribed marginal probability distribution and correlation coefficients. Measurement of the arm stretch of a precision centrifuge of 10-6 order was implemented by a high precision approach and associated uncertainty evaluation was carried out using the mentioned method and the method proposed in the Guide to the Expression of Uncertainty in Measurement (GUM). The obtained results were compared and discussed at last.

Open access

Shuiping Li, Qisheng Wu, Chong Cui, Guosen Lu, Changsen Zhang and Zhiye Yan

Abstract

TiO2/Al-MCM-41 mesoporous materials were prepared via sol-gel method by loading titania onto Al-MCM-41 mesoporous molecular sieve by hydrothermal treatment from coal-series kaolin as raw material. The TiO2/Al-MCM-41 mesoporous materials were characterized by XRD, FT-IR, HRTEM, N2 adsorption-desorption and the photocatalytic degradation of methyl orange solution under visible light irradiation. The results showed that the TiO2/Al-MCM-41 mesoporous materials possessed a high surface area of 369.9–751.3 m2/g and a homogeneous pore diameters of 2.3–2.8 nm. The titania crystalline phase was anatase, and the particles size of TiO2 increased with TiO2 content. The Al-MCM-41 mesoporous materials exhibited excellent photodegradation activity under visible-light irradiation for methyl orange.

Open access

Wang Hong, Qi-Sheng Liang, Lan-Ren Cheng, Xiao-Hong Li, Fu Wei, Wen-Tao Dai and Shi-Tong Li

Abstract

Background: Rocuronium is an alternative to succinylcholine for rapid tracheal intubation after major thermal injury and other forms of critical illness that cause denervation changes in skeletal muscle. Rocuronium may decrease the potencies of non-depolarizing muscle relaxants.

Objectives: Examine whether potency of rocuronium changed during the first month after denervation, and investigate the effects of skeletal muscle denervation on potency of rocuronium.

Methods: The denervation mouse model was developed to create denervated individual cells from the flexor digitorum brevis of the hindfoot. The skeletal muscle cells were examined at day 0 in the innervated control and days 1, 4, 7, 14, 21, and 28 in the denervation group. Nicotinic acetylcholine receptors in the cells were activated with 30 M acetylcholine, alone or in combination with various concentrations of rocuronium. Currents were recorded with a whole-cell patch-clamp technique.

Results: Rocuronium reversibly inhibited acetylcholine-activated currents in a dose-dependent fashion at different times after denervation. The inhibition concentration for the half-maximal responses of rocuronium increased 1.2- (p >0.05), 1.8-, 2.8-, 2.3-, 2.1-, and 1.9-fold (p <0.01) at day 1, 4, 7, 14, 21, and 28 after denervation, respectively, compared to that at day 0 after denervation.

Conclusion: Rocuronium dose required to achieve satisfactory clinical effects changed at different durations after skeletal muscle denervation.

Open access

Shuiping Li, Qisheng Wu, Chun Zhang, Huajun Zhu, Changsen Zhang, Xin Wang and Cancan Kong

Abstract

LiNiO2 was prepared through two-step solid-state reaction by mechanochemical method and heat treatment, using LiOH (Li2CO3) and Ni(OH)2 as starting materials. The influence of grinding speed and time, heat treatment time, and starting materials on the structure of LiNiO2 was studied. The as-milled samples and products were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that uniform as-milled samples can be obtained at grinding speed of 580 rpm for 0.5 h, using LiOH and Ni(OH)2 as raw materials. Perfect crystal LiNiO2 has been prepared by calcining the as-milled samples at 700 °C for 15 h. Composite material powders consisting of Li2Ni8O10 and LiNiO2 have been obtained using Li2CO3 as lithium source.